Weather News

Grower lathers crops in molasses to protect produce as South Australia endures consecutive frosts

Nadia Isa and Anita Butcher, Tuesday June 25, 2019 - 12:35 EST
Audience submitted image
Trees freeze over in regional South Australia where temperatures reached -5.7 degrees this week. - Audience submitted

As South Australian temperatures plummet below zero severely damaging crops, some growers are turning to creative methods to protect their produce.

The Bureau of Meteorology said yesterday's low of -5.7 degrees Celsius at Renmark in the state's Riverland was the equal-second coldest temperature on record for the town.

Meteorologist Matthew Bass said it was the region's sixth consecutive day below zero.

"Those sort of temperatures are not what we see very frequently in South Australia ... it's a very significant, severe low temperature."

Frost form when the dewpoint temperature has dropped below zero and the air is condensed to form ice crystals which then land on a surface.

Each year, frosts destroy millions of dollars worth of crops in Australia.

"If it's a very dry air mass, sometimes the temperature can drop below zero without that white frost forming, but obviously that can still do damage to plants and things that freeze," Mr Bass said.

Farmers fear impact of frost

Citrus grower Mark Doecke has had four consecutive frosts at his 30-hectare property at Sunlands about 200 kilometres north-east of Adelaide.

He has delayed picking his fruit because of the frost.

"You might have a frost or two, that's okay, but when you get four in a row and not very warm days it sort of accumulates the affect," he said.

It can damage the skin on citrus or it can freeze cells inside the orange so then it dries out when it thaws out—one's cosmetic and one's internal quality.

"When it comes to selling your fruit you'll have a dry patch on top of the orange, so you cut your nice looking orange up and it's got this big dry bit in the middle of it."

Fighting frost a sweet job

There are strategies to counteract the most severe damage from frost, including the use of frost fans and keeping the soil moist, but Mr Doecke is trying a different method.

He has turned to using the thick, sugary syrup molasses.

"Virtually molasses is just sugar product anyway so you coat the whole tree with sugar and it reduces the freezing point of the leaf and the fruit.

Nervous wait for avocado growers

At nearby Ramco on the banks of the Murray River, avocado growers were waiting anxiously to see what, if any, damage the frosts would have.

Kym Thiel, a grower and Avocados Australia tri-state director, said the tropical fruit could be severely impacted by frost.

"Avocados do hate frost, there's no doubt about that.

"At the moment we do have a very nice crop hanging out there so it is a nervous time of year for growers to get through this frosty period and come out the other side, hopefully with some fruit hanging there."

He said any damage to the crop would usually be evident within weeks, but in some cases it could be much sooner.

"In severe cases or isolated patches where there are low-lying trees you certainly see some leaf damage that afternoon or the next day."

The Bureau of Meteorology said there was likely to be a reprieve from frosts for the rest of the week, but that was little consolation this early in the season.

"We've got two more months of winter to go — it's likely that we will see some more runs of significant frost, but hopefully not as cold as we've seen."


© ABC 2019

More breaking news

Sydney Morning Herald
ABC News
National Nine News
News Limited

Display Your Local Weather

Weather News

Dust storm engulfs parts of SA, Victoria and NSW as weather bureau warns of damaging winds

18:17 EDT

An intense dust storm is sweeping through a huge area of South Australia, New South Wales and Victoria, reducing visibility and prompting a warning to drivers on outback roads.

Dust storm sweeping over SA, NSW and VIC

15:08 EDT

A large dust storm is sweeping over parts of South Australia, Victoria and NSW this afternoon.

Dubbo fish kill won't be the last as drought, fire raise extinction risk, ecologists warn

15:05 EDT

A renowned angler says a mass fish kill in the parched Macquarie River in New South Wales this week left the waterway looking like "tomato soup." Tens of thousands of fish of all sizes and species are estimated to have perished near Dubbo, in the state's west, after much-needed rain washed sediment into the river, causing dissolved oxygen levels to drop rapidly.